#!/usr/bin/env python3

# Copyright (C) 2011-2017 Damon Lynch <damonlynch@gmail.com>

# This file is part of Rapid Photo Downloader.
#
# Rapid Photo Downloader is free software: you can redistribute it and/or
# modify it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Rapid Photo Downloader is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Rapid Photo Downloader.  If not,
# see <http://www.gnu.org/licenses/>.

__author__ = 'Damon Lynch'
__copyright__ = "Copyright 2011-2017, Damon Lynch"

import pickle
import os
import errno
import hashlib
from datetime import datetime
import shutil
import logging
import locale
try:
    # Use the default locale as defined by the LANG variable
    locale.setlocale(locale.LC_ALL, '')
except locale.Error:
    pass

from typing import Optional, Tuple


from raphodo.interprocess import (BackupFileData, BackupResults, BackupArguments,
                          WorkerInPublishPullPipeline)
from raphodo.copyfiles import FileCopy
from raphodo.constants import (FileType, DownloadStatus, BackupStatus)
from raphodo.rpdfile import RPDFile
from raphodo.cache import FdoCacheNormal, FdoCacheLarge

from raphodo.copyfiles import copy_file_metadata
from raphodo.problemnotification import (
    BackingUpProblems, BackupSubfolderCreationProblem, make_href, BackupOverwrittenProblem,
    BackupAlreadyExistsProblem, FileWriteProblem
)
from raphodo.storage import get_uri


class BackupFilesWorker(WorkerInPublishPullPipeline, FileCopy):
    def __init__(self):
        self.problems = BackingUpProblems()
        super().__init__('BackupFiles')

    def update_progress(self, amount_downloaded, total):
        self.amount_downloaded = amount_downloaded
        chunk_downloaded = amount_downloaded - self.bytes_downloaded
        if (chunk_downloaded > self.batch_size_bytes) or (amount_downloaded == total):
            self.bytes_downloaded = amount_downloaded
            self.content= pickle.dumps(BackupResults(
                scan_id=self.scan_id,
                device_id=self.device_id,
                total_downloaded=self.total_downloaded + amount_downloaded,
                chunk_downloaded=chunk_downloaded),
               pickle.HIGHEST_PROTOCOL)
            self.send_message_to_sink()

            # if amount_downloaded == total:
            #     self.bytes_downloaded = 0

    def backup_associate_file(self, dest_dir: str, full_file_name: str) -> None:
        """
        Backs up small files like XMP or THM files
        """

        base_name = os.path.basename(full_file_name)
        full_dest_name = os.path.join(dest_dir, base_name)

        try:
            logging.debug("Backing up additional file %s...", full_dest_name)
            shutil.copyfile(full_file_name, full_dest_name)
            logging.debug("...backing up additional file %s succeeded", full_dest_name)
        except Exception as e:
            logging.error("Backup of %s failed", full_file_name)
            logging.error(str(e))
            uri = get_uri(full_file_name=full_dest_name)
            self.problems.append(FileWriteProblem(name=base_name, uri=uri, exception=e))
        else:
            # ignore any metadata copying errors
            copy_file_metadata(full_file_name, full_dest_name)

    def do_backup(self, data: BackupFileData) -> None:
        rpd_file = data.rpd_file
        backup_succeeded = False
        self.scan_id = rpd_file.scan_id
        self.verify_file = data.verify_file

        mdata_exceptions = None

        if not (data.move_succeeded and data.do_backup):
            backup_full_file_name = ''
        else:
            self.total_reached = False

            if data.path_suffix is None:
                dest_base_dir = self.path
            else:
                dest_base_dir = os.path.join(self.path, data.path_suffix)

            dest_dir = os.path.join(dest_base_dir, rpd_file.download_subfolder)
            backup_full_file_name = os.path.join(dest_dir, rpd_file.download_name)

            if not os.path.isdir(dest_dir):
                # create the subfolders on the backup path
                try:
                    logging.debug("Creating subfolder %s on backup device %s...",
                                  dest_dir, self.device_name)
                    os.makedirs(dest_dir)
                    logging.debug("...backup subfolder created")
                except (OSError, PermissionError, FileNotFoundError) as inst:
                    # There is a minuscule chance directory may have been
                    # created by another process between the time it
                    # takes to query and the time it takes to create a
                    # new directory. Ignore that error.
                    if inst.errno != errno.EEXIST:
                        logging.error("Failed to create backup subfolder: %s",
                                      rpd_file.download_path)
                        logging.error(inst)

                        self.problems.append(
                            BackupSubfolderCreationProblem(
                                folder=make_href(
                                    name=rpd_file.download_subfolder, uri=get_uri(path=dest_dir)
                                ),
                                exception=inst
                            )
                        )

            backup_already_exists = os.path.exists(backup_full_file_name)

            if backup_already_exists:
                try:
                    modification_time = os.path.getmtime(backup_full_file_name)
                    dt = datetime.fromtimestamp(modification_time)
                    date = dt.strftime("%x")
                    time = dt.strftime("%X")
                except Exception:
                    logging.error("Could not determine the file modification time of %s",
                                  backup_full_file_name)
                    date = time = ''

                source = rpd_file.get_souce_href()
                device = make_href(name=rpd_file.device_display_name, uri=rpd_file.device_uri)

                if data.backup_duplicate_overwrite:
                    self.problems.append(BackupOverwrittenProblem(
                        file_type_capitalized=rpd_file.title_capitalized,
                        file_type=rpd_file.title,
                        name=rpd_file.download_name,
                        uri=get_uri(full_file_name=backup_full_file_name),
                        source=source,
                        device=device,
                        date=date,
                        time=time
                    ))
                    msg = "Overwriting backup file %s" % backup_full_file_name
                else:
                    self.problems.append(BackupAlreadyExistsProblem(
                        file_type_capitalized=rpd_file.title_capitalized,
                        file_type=rpd_file.title,
                        name=rpd_file.download_name,
                        uri=get_uri(full_file_name=backup_full_file_name),
                        source=source,
                        device=device,
                        date=date,
                        time=time
                    ))
                    msg = "Skipping backup of file %s because it already exists" % \
                          backup_full_file_name
                logging.warning(msg)

            if not backup_already_exists or data.backup_duplicate_overwrite:
                logging.debug("Backing up file %s on device %s...",
                              data.download_count, self.device_name)
                source = rpd_file.download_full_file_name
                destination = backup_full_file_name
                backup_succeeded = self.copy_from_filesystem(source, destination, rpd_file)
                if backup_succeeded and self.verify_file:
                    md5 = hashlib.md5(open(backup_full_file_name).read()).hexdigest()
                    if md5 != rpd_file.md5:
                        pass
                if backup_succeeded:
                    logging.debug("...backing up file %s on device %s succeeded",
                                  data.download_count, self.device_name)

                if backup_succeeded:
                    mdata_exceptions = copy_file_metadata(
                        rpd_file.download_full_file_name, backup_full_file_name
                    )
            if not backup_succeeded:
                if rpd_file.status == DownloadStatus.download_failed:
                    rpd_file.status = DownloadStatus.download_and_backup_failed
                else:
                    rpd_file.status = DownloadStatus.backup_problem
            else:
                # backup any THM, audio or XMP files
                if rpd_file.download_thm_full_name:
                    self.backup_associate_file(dest_dir, rpd_file.download_thm_full_name)
                if rpd_file.download_audio_full_name:
                    self.backup_associate_file(dest_dir, rpd_file.download_audio_full_name)
                if rpd_file.download_xmp_full_name:
                    self.backup_associate_file(dest_dir, rpd_file.download_xmp_full_name)
                if rpd_file.download_log_full_name:
                    self.backup_associate_file(dest_dir, rpd_file.download_log_full_name)

        self.total_downloaded += rpd_file.size
        bytes_not_downloaded = rpd_file.size - self.amount_downloaded
        if bytes_not_downloaded and data.do_backup:
            self.content = pickle.dumps(
                BackupResults(
                    scan_id=self.scan_id, device_id=self.device_id,
                    total_downloaded=self.total_downloaded, chunk_downloaded=bytes_not_downloaded
                ),
                pickle.HIGHEST_PROTOCOL
            )
            self.send_message_to_sink()

        self.content = pickle.dumps(
            BackupResults(
                scan_id=self.scan_id, device_id=self.device_id, backup_succeeded=backup_succeeded,
                do_backup=data.do_backup, rpd_file=rpd_file,
                backup_full_file_name=backup_full_file_name, mdata_exceptions=mdata_exceptions
            ),
            pickle.HIGHEST_PROTOCOL
        )
        self.send_message_to_sink()

    def reset_problems(self) -> None:
        self.problems = BackingUpProblems(
            name=self.device_name, uri=self.uri
        )

    def send_problems(self) -> None:
        if self.problems:
            self.content = pickle.dumps(
                BackupResults(
                    scan_id=self.scan_id, device_id=self.device_id, problems=self.problems
                ),
                pickle.HIGHEST_PROTOCOL
            )
            self.send_message_to_sink()
            self.reset_problems()

    def cleanup_pre_stop(self):
        self.send_problems()

    def do_work(self):

        backup_arguments = pickle.loads(self.content)
        self.path = backup_arguments.path
        self.device_name = backup_arguments.device_name
        self.uri = get_uri(path=self.path)
        self.fdo_cache_normal = FdoCacheNormal()
        self.fdo_cache_large = FdoCacheLarge()

        while True:
            worker_id, directive, content = self.receiver.recv_multipart()
            self.device_id = int(worker_id)

            self.check_for_command(directive, content)

            data = pickle.loads(content) # type: BackupFileData
            if data.message == BackupStatus.backup_started:
                self.reset_problems()
            elif data.message == BackupStatus.backup_completed:
                self.send_problems()
            else:
                self.amount_downloaded = 0
                self.init_copy_progress()

                self.do_backup(data=data)


if __name__ == "__main__":
    backup = BackupFilesWorker()